This is the closest I could get; the big white ones are the males. Chinese DO make candles out of these guys.
Someone else will have more entomology and give a definitive answer but this is scale and is a sucking insect. Sort of like aphids and just as easy to control. I would pick them off if there are just a few but I worry that if these are the males where are the immature and females? Look under the leaves and at the tips of the branches. Look in the soil around the base of your rosemary. The wax covering protects them from pesticides a bit. I've heard using alcohol on a q - tip.
Kind of a cool insect, really amazing creatures how they adapt and evolve. If the infestation is severe after you are able to look more closely, take another picture of females and the young. Look at the plants nearby as well! Species Ceroplastes cirripediformis - Barnacle Scale